A relational database is a digital database that is organized based on the relational model of data. Relational databases store data efficiently by requiring the data to be organized into various tables, each of which is a collection of related data. A dataset may be a data matrix where every row corresponds to a record (or member) of the dataset, and every column represents a particular attribute of that record. The dataset usually corresponds to the contents of a single database table, or the result of a database operation that creates a table.
In order to retrieve a dataset that combines information from various tables, one has to define a “join” that specifies the relationship among the data in these tables. A “join” is a database operation that combines records from exactly two datasets to create an output dataset. A “sub-join” is a join whose result is used in another join. A “sub-join” itself can also be a complex join. A “complex join” is a join with at least one sub-join. More particularly, a complex join is a join where one or both of the input datasets come from a sub-join.
Structured Query Language (SQL) is a special-purpose programming language that is commonly used for managing data held in a relational database management system (RDBMS). SQL is one of the most widely-supported way of manipulating datasets in RDBMS. Defining a join is a complicated effort that requires advanced knowledge of SQL, the tables, data and relationships of the database to express the definition. This difficulty increases as the number of tables and columns increase.
Therefore, there is a need for an improved framework that addresses the above-mentioned challenges.